Adding upstream version 2.52.6.

Signed-off-by: Daniel Baumann <daniel@debian.org>

middleware/cors/utils.go

@@ -0,0 +1,66 @@
+package cors
+
+import (
+	"net/url"
+	"strings"
+)
+
+// matchScheme compares the scheme of the domain and pattern
+func matchScheme(domain, pattern string) bool {
+	didx := strings.Index(domain, ":")
+	pidx := strings.Index(pattern, ":")
+	return didx != -1 && pidx != -1 && domain[:didx] == pattern[:pidx]
+}
+
+// normalizeDomain removes the scheme and port from the input domain
+func normalizeDomain(input string) string {
+	// Remove scheme
+	input = strings.TrimPrefix(strings.TrimPrefix(input, "http://"), "https://")
+
+	// Find and remove port, if present
+	if len(input) > 0 && input[0] != '[' {
+		if portIndex := strings.Index(input, ":"); portIndex != -1 {
+			input = input[:portIndex]
+		}
+	}
+
+	return input
+}
+
+// normalizeOrigin checks if the provided origin is in a correct format
+// and normalizes it by removing any path or trailing slash.
+// It returns a boolean indicating whether the origin is valid
+// and the normalized origin.
+func normalizeOrigin(origin string) (bool, string) {
+	parsedOrigin, err := url.Parse(origin)
+	if err != nil {
+		return false, ""
+	}
+
+	// Don't allow a wildcard with a protocol
+	// wildcards cannot be used within any other value. For example, the following header is not valid:
+	// Access-Control-Allow-Origin: https://*
+	if strings.Contains(parsedOrigin.Host, "*") {
+		return false, ""
+	}
+
+	// Validate there is a host present. The presence of a path, query, or fragment components
+	// is checked, but a trailing "/" (indicative of the root) is allowed for the path and will be normalized
+	if parsedOrigin.Host == "" || (parsedOrigin.Path != "" && parsedOrigin.Path != "/") || parsedOrigin.RawQuery != "" || parsedOrigin.Fragment != "" {
+		return false, ""
+	}
+
+	// Normalize the origin by constructing it from the scheme and host.
+	// The path or trailing slash is not included in the normalized origin.
+	return true, strings.ToLower(parsedOrigin.Scheme) + "://" + strings.ToLower(parsedOrigin.Host)
+}
+
+type subdomain struct {
+	// The wildcard pattern
+	prefix string
+	suffix string
+}
+
+func (s subdomain) match(o string) bool {
+	return len(o) >= len(s.prefix)+len(s.suffix) && strings.HasPrefix(o, s.prefix) && strings.HasSuffix(o, s.suffix)
+}